Now "\\" at end of line forces a line break

Fixes https://github.com/kaushalmodi/ox-hugo/issues/147.

ox-blackfriday.el

@@ -87,6 +87,7 @@ Note that this variable is *only* for internal use.")
                      (item . org-blackfriday-item)
                      (latex-environment . org-blackfriday-latex-environment)
                      (latex-fragment . org-blackfriday-latex-fragment)
+                     (line-break . org-html-line-break) ;"\\" at EOL forces a line break
                      (plain-list . org-blackfriday-plain-list)
                      (plain-text . org-blackfriday-plain-text)
                      (quote-block . org-blackfriday-quote-block)

test/site/content-org/all-posts.org

@@ -1937,6 +1937,19 @@ Hash char at beginning of a continued line
 Markdown]
 
 This ! does not need to be escaped as there is no ambiguity.
+** Force line break                                        :force:line_break:
+:PROPERTIES:
+:EXPORT_FILE_NAME: force-line-break
+:END:
+From [[https://orgmode.org/manual/Paragraphs.html][=C-h i g (org) Paragraphs=]]:
+
+#+begin_quote
+Paragraphs are separated by at least one empty line.  If you need to
+enforce a line break within a paragraph, use ‘\\’ at the end of a line.
+#+end_quote
+
+Line 1 \\
+Line 2
 * Page Bundles                                                 :page_bundles:
 :PROPERTIES:
 :EXPORT_HUGO_SECTION: bundles

test/site/content/posts/force-line-break.md

@@ -0,0 +1,13 @@
++++
+title = "Force line break"
+tags = ["body", "force", "line-break"]
+draft = false
++++
+
+From [`C-h i g (org) Paragraphs`](https://orgmode.org/manual/Paragraphs.html):
+
+> Paragraphs are separated by at least one empty line.  If you need to
+> enforce a line break within a paragraph, use ‘\\\\’ at the end of a line.
+
+Line 1 <br />
+Line 2